Abstracts: ASAIO Bioengineering/tissue Engineering Abstracts
POLY(N-VINYLFORMAMIDE) AS A DRAG-REDUCING POLYMER FOR BIOMEDICAL APPLICATIONS
Blood-soluble drag-reducing polymers (DRPs) were demonstrated to have the ability to significantly increase blood flow and tissue oxygenation with no direct effect on vessel tone when injected at nanomolar concentrations in animals with normal and pathological circulation. Several DRPs, including high molecular weight polyethylene oxides (PEO), polyacrylamides, and plant-derived polysaccharides were applied in previous in vivo studies. However, the search continues for new DRPs that would be more biocompatible and mechanically stable than the synthetic DRPs and better defined and more reproducible than the natural DRPs.
High molecular weight poly(n-vinylformamide) (PNVF) was synthesized using an inverse emulsion technique and characterized using chromatography, rheology, and hydrodynamic methods. Then, the PNVF was tested in vivo to determine its ability to enhance blood circulation after intravenous injections.
The synthesis yielded PNVF with a molecular weight of 4.5x106 Da and molecular and viscoelastic properties similar to well-known DRPs. PNVF solutions demonstrated the ability to significantly reduce flow resistance in both in vitro and in vivo models. Studies of the polymer mechanical degradation caused by high stresses showed that the PNVF molecules degraded at a slower rate than the most commonly used DRP, PEO. Since PNVF is known to have no toxicity, our results warrant further investigations of this polymer for potential clinical useCopyright © 2005 by the American Society for Artificial Internal Organs